CIRCUIT BOARD ASSEMBLY WITH HIGH AND LOW FREQUENCY SUBSTRATES

摘要

A circuit board assembly (10) includes a low-frequency (LF) substrate (12), a monolithic microwave integrated circuit (MMIC (22)), electrical components (26), a high-frequency (HF) substrate (30), and an antenna (46). The LF substrate (12) is formed of FR-4 type material. The LF substrate (12) defines a waveguide (18) through the LFsubstrate (12). The MMIC (22) is attached to the top-side (14) of the LF substrate (12) and outputs a radio-frequency signal (20). The electrical components (26) are electrically attached to the LF substrate (12). The HF substrate (30) is soldered to the top side of the LF substrate (12). An opening (38) through the HF substrate (30) surrounds the MMIC (22). A vertical transition (44) guides the radio-frequency signal (20) output by the MMIC (22) to the waveguide (18). A plurality of wire bonds (40) electrically connects the MMIC (22) to the HF substrate (30) and couple the radio-frequency signal (20) from the MMIC (22) to the vertical transition (44). The antenna (46) is attached to the LF substrate (12) and configured to radiate the radio-frequency signal (20) from the waveguide (18).